The aim of this study is to investigate the association of sonographic and histological features of the plaque among each other and with biomarkers of cardiovascular risk. The predictive value of these factors concerning the long-term clinical outcome after carotid endarterectomy will also be assessed. This may help to improve the identification of patients with carotid artery stenosis who will benefit most from carotid endarterectomy. The investigators major hypothesis is that the morphology of carotid plaques is associated with objectifiable sonographic parameters, in particular with the greyscale median. Second, the investigators hypothesize that sonographic and histological plaque morphology are associated with certain biomarkers of cardiovascular risk. Identification of 'vulnerable plaques' on the basis of a peripheral blood draw and a sonographic investigation may enable the treating physician to focus resources on patients who will benefit most form therapeutic interventions for primary prevention of ischemic stroke.
The indication for revascularization of carotid artery stenoses is typically based on the degree of stenosis and the presence of symptoms. Recent evidence suggests that the risk of embolization from an atherosclerotic plaque may be associated with plaque density as assessed sonographically by determination of the greyscale median. Also, an association of serum proteins vascular endothelial growth factor (VEGF), hypoxia inducible factor (HIF) and pigment epithelium-derived factor (PEDF), matrix metalloproteinases 2, 8 and 9 with unstable plaques has been reported.
The VUCAP study will include patients undergoing carotid endarterectomy for symptomatic or asymptomatic carotid artery disease. Sonographic and serological markers of plaque vulnerability will be compared with histological features of the plaque and clinical presentation (symptomatic vs. asymptomatic). Preoperatively, the greyscale median of the plaque is assessed. Histomorphological investigation of the carotid plaques will be performed. Serological investigations will include markers of inflammation, thrombo-modulatory factors, lipid fractions and other parameters that have been associated with unstable plaques.
The aim of the present study is to assess the ability of pigment epithelium-derived factor (PEDF), vascular endothelial growth factor (VEGF), hypoxia-induced factor 1 alpha (HIF 1-α), matrix metalloproteinases 2, 8 and 9 to differentiate between vulnerable and stable carotid artery plaques. Identification of 'vulnerable plaques' on the basis of a peripheral blood draw and a sonographic investigation may enable the treating physician to focus resources on patients who will benefit most form therapeutic interventions for primary prevention of ischemic stroke.
- Carotid Endarterectomy Procedure
Intervention Desc: Carotid endarterectomy is a surgery used to reduce the risk of stroke, by correcting stenosis in the carotid artery. Endarterectomy is the removal of material on the inside (end-) of an artery.An incision is made on the midline side of the Sternocleidomastoid muscle. The incision is between 5 and 10 cm in length. Then the patients get 5000 IU heparin by the anesthesia. The internal, common and external carotid arteries are carefully identified, controlled with vessel loops, and clamped. The lumen of the internal carotid artery is opened, and the atheromatous plaque removed. The artery is closed using suture. The procedure is performed under local anesthesia. Local anesthesia, opposite to general, allows for direct monitoring of neurological status by intra-operative verbal contact and testing of grip strength. ARM 1: Kind: Experimental Label: carotid artery stenosis Description: Patients with symptomatic or asymptomatic carotid artery stenosis indicated for carotid endarterectomy, who provide written informed consent, will be included in this study. The investigators will compare patients ultrasonographic data, serum laboratory analyses and histomorphological preferances to look for biomarkers for the plaque instability.
- Observation: Case-Only
- Perspective: Prospective
- Sampling: Probability Sample
Four hundred patients with symptomatic or asymptomatic carotid artery stenosis undergoing carotid endarterectomy, after written informed consent will be included in this study. The inclusion would be done through our ambulatory care clinic.
|Type||Measure||Time Frame||Safety Issue|
|Primary||serum levels of PEDF, VEGF, HIF-1 alpha, MMP-2, -8 and -9 compared to histomorphological classification of the plaque based on AHA classification and ultrasonographic data- grey scale median (GSM)||ultrasonographical data are assessed a day before the surgery, carotid artery plaque will be taken during the surgery, whole blood on the day of operation,||No|
|Secondary||change in blood serum levels as well as protein level expression of PEDF, VEGF, HIF-1 alpha, MMP-2, -8 and -9 after plaque removal||serum blood levels are evaluated from the whole blood twice: on the day of surgery and 6 weeks after removal of the plaque||No|
Biospecimen Retention:Samples With DNA - whole blood serum carotid artery plaque